The present invention relates to 1,4-dihydropyridine derivatives having superior vasodilative and platelet aggregation inhibiting activities.
Many derivatives of 1,4-dihydropyridine are known, which are remedies for diseases of circulatory system such as remedies for ischemic heart disease, cerebral circulatory disease and hypertension. For example, 1,4-dihydro-2,6-dimethyl-4-(2-nitrophenyl)pyridine-3,5-dicarboxylic acid dimethyl ester (U.S. Pat. No. 3,644,627; hereinafter referred to as "NIFEDIPINE") and 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)pyridine-3,5-dicarboxylic acid-3-[2-(N-benzyl-N-methylamino)ethyl]ester-5-methyl ester hydrochloride (Japanese Patent Publication No. 45075/1980; hereinafter referred to as "NICARDIPINE") have already been utilized as hypotensor and coronary vasodilator. Moreover, other derivatives of 1,4-dihydropyridine having vasodilative activity together with inhibitory activity on platelet aggregation have been disclosed in Japanese Patent Applications as listed below: Japanese Patent Application Laid-open Nos. 140989/1981, 215684/1985, 226876/1985, 5076/1986, 10576/1986, 47477/1986, 197578/1986, 212581/1986 and 187468/1987.
1,4-dihydropyridine derivatives such as NIFEDIPINE and NICARDIPINE have high vasolidating activity, but they are unsatisfactory as remedy for arteriosclerosis. Therefore, researches are being made for obtaining 1,4-dihyropyridine derivatives having vasodilating activity together with platelet aggregation-inhibiting activity, capable of inhibiting platelet aggregation and curing arteriosclerosis. However, satisfactory remedies having the above-mentioned activities have not been found yet.